From: Theodore Ts'o Subject: Re: possible dev branch regression - xfstest 285/1k Date: Mon, 18 Mar 2013 13:09:28 -0400 Message-ID: <20130318170927.GA5639@thunk.org> References: <20130315222818.GA16100@wallace> <20130316150923.GA18589@gmail.com> <20130317030648.GA14225@thunk.org> <51473C8B.5070509@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Eric Whitney , linux-ext4@vger.kernel.org To: Eric Sandeen Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:54157 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751506Ab3CRRJc (ORCPT ); Mon, 18 Mar 2013 13:09:32 -0400 Content-Disposition: inline In-Reply-To: <51473C8B.5070509@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Mar 18, 2013 at 11:10:51AM -0500, Eric Sandeen wrote: > > The test could do this too, right? > > _need_to_be_root > > and: > > if [ "$FSTYP" == "ext4" ]; then > ORIG_ZEROOUT_KB=`cat /sys/fs/ext4/$TEST_DEV/extent_max_zeroout_kb` > echo 0 > /sys/fs/ext4/$TEST_DEV/extent_max_zeroout_kb > fi > > and put it back to default in _cleanup: > > echo $ORIG_ZEROOUT_KB > /sys/fs/ext4/$TEST_DEV/extent_max_zeroout_kb > > That way we'd be testing seek hole correctness w/o being subject to > the vagaries in allocator behavior. Yeah, the question is whether it would be more acceptable to put ext4-specific hacks like this into the test, or to modify src/seek_sanity_test.c so that it writes the test block-size block using pwrite at offset blocksize*42 instead of offset blocksize*10. I had assumed putting hacks which tweaked sysfs tunables into the xfstest script itself would be frowned upon, but if that's considered OK, that would be great. - Ted